This is a renewal application of the Radiation Oncology Cancer Research Center Grant (05 year). We request continuation support for investigations in cancer biology, radiation therapy physics, clinical radiation oncology, pediatric oncology, computer systems in radiation therapy, and for cooperative efforts with investigators from other departments and disciplines within Washington University that will contribute towards an understanding of tumor and normal tissue growth differentiation and destruction. With a multi-disciplinary cooperation, we will develop multi-modality therapeutic strategies. We request support for studies in molecular biology, cell biology (normal and tumor cells), both in vitro and in animal in vivo systems, and for clinical protocol studies. Programs are directed towards understanding the radiation physics requirements for improved cancer treatment and development and evaluation of computer programs for tumor patient information systems, to aid in the study of the natural history of cancer and the effects of our interventions by single or multi-modality treatment. Continued efforts will be made to translate basic biology and physics findings towards development and evaluation of clinical trials, with subsequent demonstration of evaluated techniques that will affect the medical care of cancer patients in the community.